SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccd6c93d329f1d4322949e6c5bf2e08ad8143a6ff9b12f67f3b55baa08ef935d' 
  AND token = 'EBGVCGbK+qqR54XkWf+rI/J/5Nk+0okLPuWLuEuD2vg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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