SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9206450a434054fd2df250d41a1b76a9118f9f205884dc0ed7f1f6a725a869c9' 
  AND token = 'RpdloKqQhPyLb18gMqxifq9B+iwzYfOdtHQ+Z1i9BY8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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