SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '965517cb2cbc08acdbbd5ca652b2122385699d6a4c54bb5fe64f8f898c005903' 
  AND token = 'sizuQeMJjScRi5QMhyFfuarR0qMjNN/H9Ws+Mj6TQ/Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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