SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b59e30820d3cc6582ce1879cdbe3dd0fa33eb37d74cdf22e5bd7f785145c70c1' 
  AND token = 'VUUKnkCKe+I9xPk8LwtCnJld8ifKpXH9dET6jMV4Zco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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