SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0fba735fd594fe43eca07f58359dfc32bf3ed78f51de792e0783808673e8e01d' 
  AND token = 'dH2rAb4+0IXNjtrCqzn1qBjFtadNUP4RwYFT/o8zEes=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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