SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9dc86c185684a796ddfaab10fb974da7013b100a8009c18fb3540039322b67c2' 
  AND token = '+QTIdDtSMa4mC0RQSggHWmsaGqY9Sh1mGVbL+WJY47M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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