SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33c4d0322c990f233033055a26bb50b88583df6a334c20b709b108f73026a79d' 
  AND token = 'Slgw0gg7RdK/4xBKYGipTOADCQgzYsEPtwFiHICtaGA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}