SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f99fb4d147879b3c1f8958c57b99b1d36452b8f669ccf6507db43688fb0c1855' 
  AND token = 'JbSMWu8hF/TQ9QqTBVxLsIkOCfNaovYOqUr+3ahBfA0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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