SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6fa95c66d3bdd22a5d6418023de85e773036ff5d06085da79112a49b7fdc6157' 
  AND token = 'kFjT7BC1YqpvGHZlo8wPhIjz66wv76vrFL2G2BavToc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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