SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0746f310f024a3f6ef372da59b4bbdd2751f1d9961fce0ca11c9ea083da452b5' 
  AND token = 'y92Xn+eQlKt/VnoTdh0bWo1ohAzcd+szSdcCNjmL+l4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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