SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e4624709222dd73d93edc1632fb81ca5826dcba42bf5166385d02e2b8505aaf' 
  AND token = 'nHOQgTI9Z+I6di85ydT5/ISKbqppT8HJA+nuhfhZv9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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