SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c64aefca6be6e320d001ec02770f74eaed381b515749bb8834de22314a4dd69e' 
  AND token = 'OPFj5/pwXB5HeMls9GZCzGM+9xAQx1G1LZ93TXuCASc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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