SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ce1315b763db2c8f90f42ca303747f716ea78b264bb85b7f0b7e7072ded25eb' 
  AND token = 'ZShmT8gAwFmiE/DvTYHIi10ixVVBeLBhfmjg43/9zRY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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