SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92dad0c68e6a19f6015c51cda2aa320c42eedc9bc0a65d3dca6aaaf98faab2aa' 
  AND token = 'e0KQCCJkI8hCs7U8cv3f/e1IICXN7iaOghQ3jmlVoho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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