SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f77e8c776c5e47defcef0fd78ecec5427661f928d6283ff855313e890b5fca6' 
  AND token = '7JAoz2l2+Dmz9PX/EvJ2YWx6Pda6ApPcNBs1CfD48Ao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00103

JSON explain

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