SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f6b89e3cee75ec241d4a50f30b872cbad2cd4a217dd418793f1a1eb6765cf6eb' 
  AND token = 'b2Y2T0RNPhCSFwUs8fVOuofBizx8/EiRmufgC7HjDsM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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