SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a5127d5603962f09b642a56bc402ceb357a80be3263fa488b035b0ee7b2f03c1' 
  AND token = 'e25pkOMhASCasvGtbYu2f7p+8qSRDOaaWpX5wrD8bu0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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