SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '09860a5a503c80f21a0ebbdb21c5e78247a4300eed47927676cb22e899a6b83a' 
  AND token = 'R2hDpaVz49fK9v/tf9ewzkMWWIKjbgCphafi8pmKsok=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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