SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dec7d795f678ce94c6c45f4504eab49c53123242f797b25d1c6f407a571d213f' 
  AND token = 'GzuNha/NZpXD+kOn4YVG+KAtw55eHAMONmNXmbSM/hM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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