SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f587e7568d23766ba7ee68c93106ae21d00bf0cc087dfc2cdf523e360fbfc08e' 
  AND token = 'NyJXcZtrOrZCH/qd8mMVxaTOayzWoCi97+ntcnp5FO0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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