SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5910ac65230e4ec43c3334b841d275cb8d2546e5cb25c9c177332bb433767109' 
  AND token = 'aaMog8WK0fjA18COZ0TYH6vwC0cLsiMjzn4+Hfl7fFk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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