SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '605c906c87dcbd1d45baf6fca732427bac84d20f2503b4c3a91ccc2980425fd7' 
  AND token = 'a/6fieZLYf5hnFUNUEGwg4zBJQEaPd/ECTXVLGBYUN0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}