SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ba3be01bd1afeebcfc04c756bb22559ba4a1f1ce659f3ceeed7a15b1ab122f2' 
  AND token = 'glXFbrRJlv3ECgs3qbUPtERLpCVxJhSckTJU5aUpn7E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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