Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b16fcf9221f4e0a3d0553aa2b1423f7e87e3d662d32d17d23c681e5766fda14a' 
  AND token = 'tTRHeFQNvDlaQyWPsydWPaTQ8DyO/GvP8RQ47IQagiE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}