SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2afcd711a18b1e83a673c90da3a22621ac5143481907b1644c1ea1c0235f10a3' 
  AND token = 'KjJQJFhw4jzgnoG7VjLCVks73MxP+G67rZVNFbsbVCc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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