SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fae14dddfd6c4dc1184a8c3badee6797ccf6a62c138e4937003a78b41b76228d' 
  AND token = 'p7T4uTI5MP02TEG0i/dhfKFGZbMQ8kdxQZMPOQKdMBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}