SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'cc4f7ba359d08d5e0f9a22746d290a659ee9a75df63246832d108d8704e581ec' 
  AND token = 'TVEPhnPbPAOhz93PAtuoJjmURdzKpl57o41uz5k/qsg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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