SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a86c360a3dbbfdd67f5b9dbc9cdee23456d14315c5f037d9882b2671b98339df' 
  AND token = '77o2vvu8pR/AD0hu2ZbF1PfPbqcYVMG/VJSYI/R74ng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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