SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '49b4edffe52cfd6b46df93be025a2f762ad69b169717623275f1444e4152293e' 
  AND token = '+bO81YejrPppQEUfARq+En+O946ukXW9J9C1+WAxWSE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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