SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '466ad93f4ac104b09e64a4d8808cc1e5d9021fe15979dd6fb38975ab23ca301c' 
  AND token = 'zFYrIwSE3yYEeOHVYMF+uSopZfSyi/+juvw/pP3BvUg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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