SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61ba5584a7b9c3e467abb9b9b4135cd857df78d488ae0015790d1225babec7cf' 
  AND token = 'yLTqD/mJkGuz/0tkVPwXD84jHvFpNTUX1ik5YOrfFCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}