SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d32eb0928b2206165a2ebbd2dc1d0e9ee5dd27d28ffe290b33d8b29d9fa544e' 
  AND token = 'UymlPzZn1GkgYwGQUfM5lt8lefWHTCL3FqA2xrfnVno=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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