SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c23f19740538ec081efb051414378a53c90024ba5f23c11b859c7ab066a3c6ed' 
  AND token = 'l8sLcfCVuqHNiDyqEyKZcfeKs/IG5QWF92iLhxTE2Bw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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