SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1f15cad3d1717bfbb069782cc2448c20a123c0f1e27b071a78e428fe0dd3a83' 
  AND token = 'fBAzfJD9b1vH/oxG9zKkA+XcYx/Rt63Xswi18HgpDqM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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