SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f442d250196a99a62e66d59f1bfa9c3dda11245c1e05dba4b488cb3a178fa1b' 
  AND token = 'v0Bh6klB6MGEJ+ZMdz628TsgU3hoYZWxRMMxpdDFqhc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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