SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8cdde735af4c80f9aa4a54db257b250ec1eb52aa5b775f8b8613b0de767db119' 
  AND token = 'Jvvh2tOPEV0tqRns+WTlKZYccjWypAQi1HVOBnEOc10=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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