SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1cf577d0bd17ecb61e17ed18e44e84ecb5134a5009ea7e90b6fd322221868da' 
  AND token = 'IOiRrxoi+ICxKPn4AeZGjaHsA8KkVHefU1E/zVH+npY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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