Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b8c5b85df3ae33d6ab0a582365ce8452688d13d1d8e38e41ab85fec14bd21d53' 
  AND token = 'rwND4BQ4ZPN4M1+ajAFFHDkthk3/8IULqxNmhtNV2/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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