SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4baf1652ae44809673b3c77dbabceccff3135c43df34af96f6561b99103df982' 
  AND token = 'YAFXX4DKisR1jTAoK6FncNmSWA4p9L/EOfGXF0iPW9I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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