SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5af05a6617d601965d708761aa3ba37ac8f2d30df33939e6ea013086d97f410a' 
  AND token = 'ohrLTvskhRpxePsB9AAA1QVCtpHtFq2Da6LXKh+rivg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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