SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '88438b02c1e7f3e32cf240ee4c67d2d9c5aa7be1f34ed88789771817409946be' 
  AND token = 'zgmq+vzhkbCa3gwRNn9f6fx2JKYSoKr0rd8+M6dvzsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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