SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdfdc3707c96d4b66851fff8ca1339db73af1420c592f2267062bab7ace1303a' 
  AND token = 'jvj0VUWVAxYkPtgo/KGkJtibFduX7rBh2HwdNtNUHiE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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