SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8395c4921e7844ddd6be7458779ce5ab6f8051cfc7c9528731a945c2f30661ed' 
  AND token = 'j5FJuQR2l6rkPkqMolbNmChxZEKT8Q8Lug0x+vzpp+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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