Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3ad375f981de80f3d3a19439f9f698bee252fc42674641e3e3fbdd0b326f9ca' 
  AND token = 'VytkeWeFYc0ZsVFSfsmS6xtoG3mKpjc0ovVv+GOsOyg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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