SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1885c70e65daccf1213ee9d73004fe1026ec101b3c09df1588a0469094d3fb3d' 
  AND token = 'NB8zwVLdD0jjWmmVLEQSgXJ23d2Gj8FZAqoPvwHCykY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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