SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0adb2ce8ad079203008ad589b87d169a2c2431f2a72a1ee7934060e444dbd645' 
  AND token = 'MHIRfKeO21T54R/q7z/2msbDSooZuPiCtUDyOQiF3Qk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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