SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f176ebb7892ef887126a72d85123043eecc5474a0fa671d02bb86e5c70f60db0' 
  AND token = 'P1xyvVqjAuujj8/sS2JutzbkIBiM/kdSi3uNzSUmxPY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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