SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85be2ffcf10496c732b276aa68db683c531a9a19b2000f2200f5483605111eed' 
  AND token = 'AjhOsWRvw1Ll3k0tRLJpvZFR9ZfKpmT6h8m+q5+7fFI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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