SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '039f2490ad29c2258737396a68c0db1aa86ed9bea2afb309452821f60ac6ab23' 
  AND token = 'TySQzx7PVZOUxHZBYeB+1mfkPKU8lHVUqAIYEYosmgQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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