SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30393eb3167f9df351d46283a82564be154045cc983490c2d02e920ee90cc831' 
  AND token = 'SC6A7HefAtgzZr2MBB9jR2haJZg1KbcroJtwCIazY+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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