SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f57417cdd991aabca518bedfc2be3dd8dab1ec92de5e1737ee0cb1240df0c130' 
  AND token = 'dfPZUjkJ4WyzOubSNBzFFvEPjiNpgfjRR+0B51FFQhA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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