SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4619897ae2c38c0417863e9736b3de5506076b1703e39eeafa947d94bc405f3e' 
  AND token = 'ojOHbIAIRutn0uGWuaGIUakWmWzDuYPPKQNv268w4IM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

JSON explain

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