SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58267e2ee5ce17e497eeb48fb07c18544bf29ead1a3b4ff728d592917181a4f9' 
  AND token = 'EjWu/wi/Z/SXJVMyHbTw3iWvV2h6G4zLOPA3ZrzU0tw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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