SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a14a35627c8d58f9ea4b7e2cf36a8b6a6712bd58d26ca87c3a4a40914bcbd044' 
  AND token = '+Uej3Qpz3Csf5KoBqOj4Dzz8xYdnPQagnMTQYynJRPg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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