SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0d46d549d8d9a7e8d29f6f8ea156aef35e713f26e5bb4b9421e328ad10f7edf' 
  AND token = '/Cez37vv6iLc5fxCiWqwXcADLPQns6lgpwHBKkItWrE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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