SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85b413a08cf8dde1240e6c360a9ef3c16958437a2a64c00c6175d93549b210bd' 
  AND token = 'wc+BRNotOPbNgGQa8PE8x4OJIKvfq9bshIGK+mzZ8ow=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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