SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1b9523e98a108bf53f6be88bb796c5e40410e73c5f16d06971a3a422c05fc604' 
  AND token = 'B7SzQ+Ymaiw+EksGq3dNi4DZi9IXmm56f59BUt2LAFA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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