SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '136fdf9851c79858d56b8bb95eaad977d6ad677852bac59e847d160d7324912a' 
  AND token = 'eyqNevu03PNpLe7+dCQhLZUk/MC2F/yLYjI7QYFhHSY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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