SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0c16512728ed17b1c543c369ecd95ee5aff19eade1269171f1e9c386038646b9' 
  AND token = 'X1zPb+6VL/JdCuo7mTYz7S8I24wwL1cOP5851UPblxQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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