SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6993d29dc198fa7d74ae38166a1f66c2e6876764fbe75a2dc554d692e6cbda6f' 
  AND token = 'aKicLDoMZrnUHNJC9Ae3cDD5Gg2fvKQ6Wm4YPgeafOs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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