SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fba0010e48ecd2c3c7193ff8a7cead491f76bf7f0cd375fa4d05619ba785adea' 
  AND token = 'kHiRHTSvK6O1mrSEmc6RZLqCpHJq4bXW4H0mqs13ngk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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