SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be414df28a01ee6357d8cfc5c47ca0f33da08ce959573cb15013df37d49d7198' 
  AND token = 'vPVyRg3ZlKrekO4TcOnj8DrCTBUmiWpEvYORlrjMhws=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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