SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1d2bd521c9b3cb4b6090cf025bd45f4070e4bead3a73babee1667c69f7ecb5d' 
  AND token = '2PnmW9sgmrNVX8mXJcRS5HIaZPgR3COY5nQy0TAvQic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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