SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82364b6a93bea687b30597d626d92c39f53ee20b67aa9cb92ef147bb538c508b' 
  AND token = 'SlF82L3SRVJaz8sB+4r7shZLX/3gUI8mgcZUpv4g51U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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