SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a47edd89ee5e6963a14d574b8035423559bdb11e6439c7f13cb6acf1ea974bc1' 
  AND token = 'YKw+SRtrGKNjZ+w8+ZwLI/q+9xn+1Jruzr02oQIC8qE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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