SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d8defe84753abb7564c500c67fc1331992695bdc7605d8057d1e8d8ef47f5f5' 
  AND token = 'wHG35+SdQIT8StWkmCkt8Z/TPEMdWffK/xcdQlWWwx0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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