SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a808320881feaad86b69a51c40842a976ad8beea4f018fbc5ad6633d1ef87a1c' 
  AND token = 'akwJkYusMqI3lLKhaphAK8DUYq5iJxc+X7HqlHAxfqc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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