SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a98881e2e41186e9656148801169efca921597ffa665d65be9b6533f7606f58' 
  AND token = 'g3Fdh4YP9onmRHA07M+RtSfN3wEYFVBHDHMXiDOuAzo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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