SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7b9d57ba015a837f7e98e353128ebbf690ce107fe198928368dd0d11fd9a025' 
  AND token = '+4LeRzvMEMurxJCOUXXXXsbKezm7zPR2/qQfe16eBcg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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