SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '195a5ef1899905af395871fe4d62eab53c6f8b42891650269ab2d70c2237c098' 
  AND token = 'XAFYtlyVZg549ChYPtvH82YbVHMuLmefS/85WTVXXoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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