SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7902130bb5600ecf61b79a15c8477c42899dd5a603c5702d57154f45598064cd' 
  AND token = 'USOBcNTBWsO74NYqXXqZgHSjERFvfpy/bITkuQcmtDI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00078

JSON explain

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