SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eac0b32ac62b6aeca6864db6a520d9223155fbe68bda88f31cb2b004219c88a5' 
  AND token = 'MjAB2hWFgDnbiZF9O7f4kv39e7L5fmUUrzvPfaFiluo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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