SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1de305fbcc83d33e2671684b6a3e611676434635809f375bc4841d525abe4fcc' 
  AND token = 'KLDG3nDZrbCzC+r2cC5lyNJOB/udFbImEstMJk9QLxE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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