SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b5e87066afc14ad88463fcbc72c76219a4f7fe46fd4c1e382f707936ebdcb3f7' 
  AND token = 'WrTcqiXeh3459e1LXYmBqd6hdzRElqvnVMNUr51dtVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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