SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afd9446f29a5ab777b99de18b8dc450e7d0f933dc04fa294a262045d8a653e26' 
  AND token = 'V1r4eX1/hFpCzaSwsNtXZ7W0ctpkC93GwCcUNzxpKjQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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