SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '89788f95e1c26d5134c8f9278b162e012ad8914b4d4508ee25828bd60809c226' 
  AND token = 'lhxDIdWdEhaf2uM9AW0R78j4xMCbkZHUR9KDSoeDyKw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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