SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4adbf8ae23738c5d8f2c3cbbc01a49db8890c823b00c635e382b13f9dca3af4' 
  AND token = 'cUGgx9M5U0OSPQKinu1qVdkyzSuYxQd/KgMIlV+I2f4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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