SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a32478768662650e9f05c9bbc9df4940762b5ddef2ace31bfd1443bdd2b7049' 
  AND token = 'jZ2Lr3pJ+8RrzdK/vFGugHJJS+yyiIn5YcNF3LSRGUQ=' 
  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"
    }
  }
}