SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b3a686466bc4d99687f2a43524b9d180ca00f4a1b37cd5f05331315b3230980' 
  AND token = 'CKPiCvHyI8fu55yb9Wm5ZmCJGCLix1a82LSj7t2HTwc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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