SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ead18571e9bf94c08f5d897a7ad71be8eb0e5593fa094a50f075c55195472c44' 
  AND token = 'HTXUNdYALoAs3nh5N6/2qm8Q/UeLXrdXwnh1D2P2Z7M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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